The present invention is particularly concerned with the distribution of frangible or delicate products, such as cereal bran flakes, into a storage or surge bin. Conventionally, such storage or surge bins are rectangular in cross section, open at the top, and several feet in depth. The floor of the bin is usually a belt conveyor adapted to move product in the direction of the bin discharge end. A picker or doffer at the discharge end is adapted to unload product conveyed to such end by the floor conveyor. One purpose of such bins is to provide a uniform feed to downstream equipment, for instance a dryer.
Loading a surge bin in this invention is complicated by the fragility or brittleness of the product. It is known to use a vibrating distributing conveyor mounted across the top of the bin on a trolley which moves lengthwise back and forth, along the bin. The position of the trolley is controlled by a sensor system which detects the position of the product pile in the bin. In operation, product is fed onto the vibrating distributing conveyor at a point to one side of the bin. The distributing conveyor is in the shape of a shallow pan, and vibration of the pan causes the product to flow towards a slot in the bottom of the pan, and to drop through the slot into the bin.
One problem in loading a storage or surge bin is transferring the product (e.g., cereal bran flakes) from a source to the vibrating pan conveyor. In practice, this may be done by using a hopper which deposits product onto what is referred to as a reverse wrapped belt conveyor. This type of belt conveyor has a delivery end above the vibrating pan conveyor feed point, the delivery end being adapted to travel with or follow the vibrating pan conveyor as the latter moves along the bin length. The belt is of the continuous type, with a stationary drive drum. As the belt delivery end moves towards or away from the drum, slack in the belt is taken up or given by a pair of drums beneath said delivery end defining a reverse loop in the belt, wherein the pair of drums and reverse loop are adapted to move with the belt delivery end and in the same direction the belt delivery end is moving. Obviously, the apparatus is extremly cumbersome, subject to high maintenance costs, and unsanitary in that it is hard to clean, among other disadvantages.
Various other arrangements have been proposed to transfer product from one conveyor to another. One example is a Greulick U.S. Pat. No. 2,833,390, which is provided with means to tip or canter the conveyor belt so that product on the conveyor belt can fall off of or be displaced onto a second belt positioned along the lower side of the tipped or cantered belt.
A Bruce et al U.S. Pat. No. 3,138,408 and a Tipton U.S. Pat. No. 3,153,477, both disclose use of a diverting blade on a belt to transfer product from the belt. Jepsen U.S. Pat. No. 3,827,777 shows the use of an air cushion for diverting product. In the '408 patent, means are provided for directing air beneath the diverting blade to prevent fibers from passing under the diverter and jamming the belt. This use of air alone at sufficiently high pressure to prevent jamming, with lightweight cereal product on the belt, would be likely to inadvertently scatter the product off the belt rather than direct it onto a second belt.
In the '477 patent, means are provided for producing a hump in the belt immediately ahead of the diverter blade or deflector. The purpose of this is to prevent flat pieces of mail from passing underneath the deflector or blade. The system would not likely be effective with the diversion of particulate cereal products.
Similarly, the use of an air cushion as in the '777 patent would tend to scatter product off the belt, and would not be suitable in the present process.